Optical heartrate monitoring systems typically use an optical radiation sensor that is sensitive to visible or infrared (IR) light to detect the flow of hemoglobin in blood in the human body. In some systems, a subject wears some form of monitoring equipment or a sensor is positioned to contact an extremity such as a finger or earlobe. Other non-contact optical heartrate monitoring systems detect hemoglobin flow by measuring brightness variations in a subject's face. While existing systems can perform satisfactorily in many situations, they are not generally well adapted for usage scenarios in which the subject is expected to be active. For example, contact systems can often be cumbersome and impractical for application to athletes and fitness enthusiasts, and also ambulatory medical patients, while non-contact systems typically require the subject to remain still as the heartrate monitoring is performed.
This Background is provided to introduce a brief context for the Summary and Detailed Description that follow. This Background is not intended to be an aid in determining the scope of the claimed subject matter nor be viewed as limiting the claimed subject matter to implementations that solve any or all of the disadvantages or problems presented above.